Sunday, March 15, 2015

Secret Designer Babies via Gene-editing Science

Despite worldwide near-unanimity of its illegality, scientists have covertly, for the first time, genetically modified the DNA of human egg cells such that human embryos could be created of a specific pre-determined design, such as superhumans, by governments or wealthy individuals.

The research was carried out on ovary cells taken from a woman with inherited ovarian cancer to investigate the possibility of eventually using gene-editing to produce IVF embryos free of the familial disease. The results are yet to be published.

Editing the chromosomes of human eggs or sperm to create genetically modified IVF embryos is illegal in Britain and many other countries because of concerns about safety and the possibility of the technique being used to create genetically enhanced “designer babies”.

Several teams of researchers around the world are believed to be working on ways of modifying the chromosomes of human egg cells with a view to moving towards “germ-line” gene therapy, as the process is called. Germ-line refers to the “germ” cells – sperm and eggs – that pass on genes to future generations.

The work was carried out last year by Luhan Yang, a researcher working in the lab of the veteran Harvard geneticist George Church. But the study has not been published in a scientific journal and Dr Yang was unavailable for comment.

Professor Church emphasised that the work was purely experimental. . . .

Amidst rumours that precise gene-editing techniques have been used to create designer human embryos, researchers have called for a moratorium on the use of the technology.

Geneticist Xingxu Huang of ShanghaiTech University in China has sought permission from his institution's ethics committee to genetically modify discarded human embryos.

Precise gene-editing techniques in recent years use enzymes called nucleases to snip DNA at specific points and then delete or rewrite the genetic information at those locations. Methods like the CRISPR are simple enough to be done in a fertility clinic.

Geneticist Dana Carroll of the University of Utah in Salt Lake City says, "Germline genome alterations are permanent and heritable, so very, very careful consideration needs to be taken in advance of such applications."

Rumours about such experiments have been circulating the web for quite some time now and critics of the work say that such experiments could be used to try to alter the genetic quality of humans, a practice and belief known as eugenics.

Edward Lanphier, president and chief executive officer of California-based Sangamo BioSciences Inc, and senior author of the commentary published in the science journal Nature call for a self-imposed research moratorium as the work crosses an ethical line. “Humans are not rats or other (experimental) organisms, and this is not something we want to do,” Lanphier said in an interview with Reuters quotes Zee News. “The research should stop.”

According to Lanphier, who is also the chairman of the Alliance for Regenerative Medicine in Washington DC, “Such research could be exploited for non-therapeutic modifications” and a “public outcry about such an ethical breach could hinder a promising area of therapeutic development.”

Lanphier added that genome-editing can itself introduce DNA errors and “the precise effects of genetic modification to an embryo may be impossible to know until after birth. Even then, potential problems may not surface for years.”

Known as germline modification, edits to embryos, eggs or sperm are of particular concern because a person created using such cells would have had their genetic make-up changed without consent, and would permanently pass down that change to future generations.

Germline gene editing is already banned by law in many countries — a 2014 review by Tetsuya Ishii, a bioethicist at Hokkaido University in Sapporo, Japan, found that of 39 countries, 29 have laws or guidelines that ban the practice. But the development of precise gene-editing techniques in recent years has brought fresh urgency to the issue. These techniques use enzymes called nucleases to snip DNA at specific points and then delete or rewrite the genetic information at those locations. The methods are simple enough to be used in a fertility clinic, raising fears that they might be applied in humans before safety concerns have been addressed.

Ishii worries about countries such as the United States: there, germline editing is not banned but requires government approval, but such restrictions have a history of being circumvented, as in the case of unproven stem-cell treatments. He is also concerned about China, which prohibits gene-editing of embryos but does not strictly enforce similar rules, as shown by failed attempts to curb the use of ultrasound for sex selection and to stamp out unauthorized stem-cell clinics. China is also where gene-editing techniques in primates have developed fastest. “There are already a lot of dodgy fertility clinics around the world,” he says.